Mechanisms of negative inotropic effects of class Ic antiarrhythmic agents: comparative study of the effects of flecainide and pilsicainide on intracellular calcium handling in dog ventricular myocardium.

@article{Kihara1996MechanismsON,
  title={Mechanisms of negative inotropic effects of class Ic antiarrhythmic agents: comparative study of the effects of flecainide and pilsicainide on intracellular calcium handling in dog ventricular myocardium.},
  author={Yasuki Kihara and Moriaki Inoko and Noboru Hatakeyama and Yasunori Momose and Shigetake Sasayama},
  journal={Journal of cardiovascular pharmacology},
  year={1996},
  volume={27 1},
  pages={
          42-51
        }
}
We studied the subcellular mechanisms responsible for the negative inotropic effects of the two Ic drugs flecainide and pilsicainide. Aequorin luminescence (Ca2+i) and isometric tension were recorded simultaneously in isolated trabeculae from the dog ventricle. In isolated myocytes from the same ventricle, the slow inward current (ICa) was recorded. Both flecainide and pilsicainide decreased peak Ca2+i, peak tension, and peak ICa concentration dependently. Each effect with flecainide was more… 
Negative chronotropic and inotropic effects of class I antiarrhythmic drugs assessed in isolated canine blood-perfused sinoatrial node and papillary muscle preparations
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Several variations and interactions within a specific environment and underlying disorder might be of pharmacological or/and pharmacokinetic origin, making analysis of the true liability of the class I drugs very difficult when adverse effects occur.
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TLDR
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Sevoflurane Enhances Negative Inotropic Action of Pilsicainide and Flecainide
Pilsicainide and flecainide, which have a relatively low negative inotropic action, are sometimes used for the treatment of intraoperative atrial fibrillation. Sevoflurane, commonly used for general
The cardiac work-loop technique: An in vitro model for identifying and profiling drug-induced changes in inotropy using rat papillary muscles
TLDR
It is demonstrated that the work-loop technique can provide an important novel method with which to assess detailed mechanisms of drug-induced effects on cardiac muscle contractility and changes in work loop shape detailing for example the activation, shortening or passive re-lengthening have been linked to the mechanism of action of a compound.
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